设置
快速交货
免运费
国际贸易术语
支付类型
市场产品
This caused by a lack of input path-to-ground. All op-amps (the in-amp input stage is an op-amp) must have a ground path for their two inputs. This is because all amps have a small DC current component and must be able to sink or source that somewhere, usually via ground. If not allowed to return to ground, these input currents will bring the voltage at the inputs to a point where the amplifier no longer works correctly. The three figures on the left are the most common erroneous connections of the inputs. Those are examples of what not to do. Instead, connect the the inputs like the circuits on the right. Be sure to pay attention to the value of the resistors. Offset current x resistor values = offset voltage (Vos), normally desired to be low. Check for switches or multiplexers at the previous stage that, when turned off, also cut off the path to the ground for the in-amps inputs.
